ASoC: Add simplfied device registration for Atmel SSC devices

Since the SSC is already being registered as a device under arch and
the DMA and SSC hardware are pretty much the same provide a simplified
device registration function for the Atmel SSC which will add the
ASoC-specific devices within the ASoC code, parenting the SSC device
off the actual SSC device. Also use it in the sam9g20-ek driver.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>

3 files changed, 62 insertions, 3 deletions

diff --git a/sound/soc/atmel/atmel_ssc_dai.c b/sound/soc/atmel/atmel_ssc_dai.c
index eabf66af12cd..5d230cee3fa7 100644
--- a/sound/soc/atmel/atmel_ssc_dai.c
+++ b/sound/soc/atmel/atmel_ssc_dai.c
@@ -789,13 +789,14 @@ static struct snd_soc_dai_driver atmel_ssc_dai[NUM_SSC_DEVICES] = {
 
 static __devinit int asoc_ssc_probe(struct platform_device *pdev)
 {
-        return snd_soc_register_dais(&pdev->dev, atmel_ssc_dai,
-                        ARRAY_SIZE(atmel_ssc_dai));
+        BUG_ON(pdev->id < 0);
+        BUG_ON(pdev->id >= ARRAY_SIZE(atmel_ssc_dai));
+        return snd_soc_register_dai(&pdev->dev, &atmel_ssc_dai[pdev->id]);
 }
 
 static int __devexit asoc_ssc_remove(struct platform_device *pdev)
 {
-        snd_soc_unregister_dais(&pdev->dev, ARRAY_SIZE(atmel_ssc_dai));
+        snd_soc_unregister_dai(&pdev->dev);
         return 0;
 }
 
@@ -809,6 +810,56 @@ static struct platform_driver asoc_ssc_driver = {
         .remove = __devexit_p(asoc_ssc_remove),
 };
 
+/**
+ * atmel_ssc_set_audio - Allocate the specified SSC for audio use.
+ */
+int atmel_ssc_set_audio(int ssc_id)
+{
+        struct ssc_device *ssc;
+        static struct platform_device *dma_pdev;
+        struct platform_device *ssc_pdev;
+        int ret;
+
+        if (ssc_id < 0 || ssc_id >= ARRAY_SIZE(atmel_ssc_dai))
+                return -EINVAL;
+
+        /* Allocate a dummy device for DMA if we don't have one already */
+        if (!dma_pdev) {
+                dma_pdev = platform_device_alloc("atmel-pcm-audio", -1);
+                if (!dma_pdev)
+                        return -ENOMEM;
+
+                ret = platform_device_add(dma_pdev);
+                if (ret < 0) {
+                        platform_device_put(dma_pdev);
+                        dma_pdev = NULL;
+                        return ret;
+                }
+        }
+
+        ssc_pdev = platform_device_alloc("atmel-ssc-dai", ssc_id);
+        if (!ssc_pdev) {
+                ssc_free(ssc);
+                return -ENOMEM;
+        }
+
+        /* If we can grab the SSC briefly to parent the DAI device off it */
+        ssc = ssc_request(ssc_id);
+        if (IS_ERR(ssc))
+                pr_warn("Unable to parent ASoC SSC DAI on SSC: %ld\n",
+                        PTR_ERR(ssc));
+        else
+                ssc_pdev->dev.parent = &(ssc->pdev->dev);
+        ssc_free(ssc);
+
+        ret = platform_device_add(ssc_pdev);
+        if (ret < 0)
+                platform_device_put(ssc_pdev);
+
+        return ret;
+}
+EXPORT_SYMBOL_GPL(atmel_ssc_set_audio);
+
 static int __init snd_atmel_ssc_init(void)
 {
         return platform_driver_register(&asoc_ssc_driver);
diff --git a/sound/soc/atmel/atmel_ssc_dai.h b/sound/soc/atmel/atmel_ssc_dai.h
index 392a46953112..5d4f0f9b4d9a 100644
--- a/sound/soc/atmel/atmel_ssc_dai.h
+++ b/sound/soc/atmel/atmel_ssc_dai.h
@@ -117,4 +117,6 @@ struct atmel_ssc_info {
         struct atmel_ssc_state ssc_state;
 };
 
+int atmel_ssc_set_audio(int ssc);
+
 #endif /* _AT91_SSC_DAI_H */
diff --git a/sound/soc/atmel/sam9g20_wm8731.c b/sound/soc/atmel/sam9g20_wm8731.c
index cf029a89ef76..293569dfd0ed 100644
--- a/sound/soc/atmel/sam9g20_wm8731.c
+++ b/sound/soc/atmel/sam9g20_wm8731.c
@@ -205,6 +205,12 @@ static int __init at91sam9g20ek_init(void)
         if (!(machine_is_at91sam9g20ek() || machine_is_at91sam9g20ek_2mmc()))
                 return -ENODEV;
 
+        ret = atmel_ssc_set_audio(0);
+        if (ret != 0) {
+                pr_err("Failed to set SSC 0 for audio: %d\n", ret);
+                return ret;
+        }
+
         /*
          * Codec MCLK is supplied by PCK0 - set it up.
          */